User Manual

MAX6643/MAX6644/MAX6645
Automatic PWM Fan-Speed Controllers with
Overtemperature Output
______________________________________________________________________________________ 11
MAX6643_A_
TH1
16
15
14
13
12
11
(TACHOMETER MODE)
(TACHOMETER MODE)
TO OVERTEMPERATURE ALARM
10
9
TL2
TL1
FANFAIL
TO FANFAIL
ALARM
TO FANFAIL
ALARM
TACHSET
FULLSPD
GND
DXP
V
DD
V
DD
(+3.0V TO +5.5V)
+V
FAN
(5V OR 12V)
1
2
3
4
5
6
7
8
TH2
OT1
OT2
PWM_OUT
FAN_IN1
FAN_IN2
OT
4.7kΩ
4.7kΩ
4.7kΩ
N
N
MAX6643_A_
TH1
16
15
14
13
12
11
(TACHOMETER MODE)
(TACHOMETER MODE)
TO OVERTEMPERATURE ALARM
10
9
TL2
TL1
FANFAIL
TACHSET
FULLSPD
GND
DXP
V
DD
V
DD
(+3.0V TO +5.5V)
+V
FAN
(5V OR 12V)
1
2
3
4
5
6
7
8
TH2
OT1
OT2
PWM_OUT
FAN_IN1
FAN_IN2
OT
4.7kΩ
4.7kΩ
4.7kΩ
Figure 6. Using Two MAX6643s, Each Controlling a Separate Fan